Chronograph timepiece

ABSTRACT

A chronograph mechanism mounted on the gear train of a timepiece movement. A coupling device and a locking device on the driven end of the mechanism are operable for synchronistic movement; a braking device on the terminal end of the mechanism operates to secure the gear train at both ends when the mechanism is disconnected from the movement so as to prevent any slippage of the gears.

United States Patent [191 Dubois et al.

[ CHRONOGRAPH TIMEPlECE [75] inventors: Gerald Dubois; Francois Berthoud, both of Le Lieu, Switzerland [73] Assignce: Ebauches S.A., Ncuehatel,

Switzerland [22] Filed: Mar. 8, 1973 [21] Appl. No.: 339,299

[30] Foreign Application Priority Data Mar. l5 1972 Switzerland .v 760/72 [52] U.S. Cl. 58/77 [51] Int. Cl. G04f 7/04 [58] Field of Search 58/74, 77

[56] References Cited UNITED STATES PATENTS 3,()45,4l8 7/1962 Heuer 58/74 Oct. 22, 1974 3,543,506 l'Z/l970 Duhois ct ztl v. 58/74 3.653.20 4/1972 Ogawa et al. 58/74 Primary ExaminerGeorgc H. Miller, Jr. Attorney, Agent, or Firm-Silverman & Cass [57] ABSTRACT A chronograph mechanism mounted on the gear train of a timepiece movement. A coupling device and a locking device on the driven end of the mechanism are operable for synchronistic movement; a braking device on the terminal end of the mechanism operates to secure the gear train at both ends when the mechanism is disconnected from the movement so as to prevent any slippage of the gears.

14 Claims, 6 Drawing Figures PArEminnmzzmm sum 10f 3 FIG. 3

PAIENTEB 001221974 sums-er;

FIG

1 CHRONOGRAPH TIMEPIECE BACKGROUND OF THE INVENTION The present invention has for its object a chronograph timepiece.

The timepiece of the invention is characterized by a chronograph mechanism mounted in derivation on the gear train of the timepiece movement. The mechanism includes a coupling device and a locking device provided on the driven end thereof which is connected to said gear train; the coupling device and locking device are operable for synchronistic movement. A braking device is provided on the terminal end of the mechanism such that when the chronograph mechanism is disconnected from the timepiece movement so as to isolate one from the other, the gear train of the chronograph mechanism is held at its ends by the locking and braking devices so as to prevent any slippage of the gears.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings show, by way of example, one embodiment of the invention.

FIG. 1 is a plan view of a movement of a chronograph watch in which only the elements necessary to the understanding of the invention have been represented.

FIG. 2a and 2b constitute together a sectional view taken along the line 11-11 of FIG. 1, on an enlarged scale.

FIG. 3 is a sectional view of a portion of FIG. 2a, taken on an enlarged scale.

FIG. 4 is a plan view of a portion of the control mechanism of the chronograph of the invention, being illustrated in a position different from the one represented in FIG. 1, and

FIG. 5 is a bottom plan view, of the mechanism of the chronograph of the invention in which only the gear train constituting the gear train of the chronograph has been represented.

DESCRIPTION OF THE PREFERRED EMBODIMENT The watch movement represented comprises a chronograph mechanism, the frame of which is formed by two plates 1 and 2 and by several bridges as 3 and 4. The frame is secured to the base plate of the movement which is not represented in the drawing.

The gear train of the chronograph, which is mounted in derivation on the gear train of the movement, comprises a second wheel 5, two intermediary elements 67 and 8-9, and intermediary wheel 10 and a minute wheel 11 which makes one revolution per 30 minutes, two intermediary elements 12-13 and 14-15, an intermediary wheel 16 and an hour wheel 17.

The second wheel 5 is coaxial with a shaft 18 carrying a second hand not shown. The wheel 5 is driven by the intermediary of a coupling mechanism which is disclosed hereafter, combined with a locking mechanism, to ensure connection between the wheel 5 and a wheel 19 in meshed engagement with an elongated pinion 20,

cooperates with a bearing surface 25, of corresponding shape, of the end of the hub 21.

Owing to this arrangement, when the mechanism as disclosed is in a position of engagement, as represented in the drawing, the wheel 19 is rigid with the wheel 5 owing to the axial force exerted by these two wheels one on the other under the effect of the spring 23; the wheel 19 also is rigid with the cannon 22 and consequently with the shaft 18, owing to the axial force exerted by the wheel 19 and by the cannon 22 one on each other, also under the effect of the spring 23.

The coupling mechanism as disclosed comprises a control element 26 constituted by a small circular plate positioned in a recess of plate 2 corresponding in shape to that of the element 26. Control element 26 is moveable axially under the effect of a force exerted thereon by three conical pins 27 disposed at one to each other. Pins 27 pass through holes 28 provided in the small plate and are carried by a sliding element 29 moveable transversally. The sliding element 29 is part of the control mechanism of the chronograph which will be disclosed hereinafter. When the pins 27, acting on the edge of the holes 28, lift the small plate 26, the plate 26 in turn lifts the spring 23 and the wheel 5, so that the axial force exerted by the spring on the shoulder 18a of the shaft 18 terminates. Termination of the axial force on shoulder causes the wheel 19 to disconnect from the second wheel 5 on the one hand, and from the cannon 22 on the other hand. Moreover, the wheel 5 bears axially against a portion 2a of the plate 2, to lock the wheel 5. In this manner, the coupling mechanism is combined with a locking mechanism which locks the wheel 5 as soon as the gear train of the chronograph is disconnected from the gear train of the movement.

The disconnection of the shaft 18 enables the same to be reset to zero by means of a heart piece 30, without the wheel of chronograph being driven.

The minute wheel 11 is force fit on a shaft 31 carrying a minute hand, not shown by the intermediary of a coupling mechanism comprising a spring 32 interposed between the wheel 11 and the shoulder 31a of the shaft 31. Spring 32 forces the wheel 11 against a shoulder 33a of a sleeve forced on the shaft 31. A control element constituted by a small plate 34 similar to the small plate 26 of the coupling mechanism which has been disclosed hereinabove is controlled by a sliding element 35 associated with the control mechanism of the chronograph, also disclosed hereinafter. The sliding element 35 carries conical pins 36 (FIG. 1), acting on the small plate 34 for lifting it axially and permitting it to act on the spring 32 so as to disconnect the shaft 31 from the wheel 11 during the resetting of the same to zero; this resetting operation is effected by means of a heart piece 37.

It is to be noted that, when the spring 32 is lifted by the control disc 34, producing disconnection of the shaft 31, the wheel 11 is forced against the edge of the endstone, 38, of the upper bearing of the shaft 31, to brake wheel 11. This operation is such that, when the chronograph is stopped, the shaft 31 of the minute indicator is braked.

The wheel 17 drives the hour shaft 39, by the intermediary of a coupling mechanism comprising a spring 40 forcing the wheel 17 against a shoulder 41a of a cannon 41. Cannon 41 is carried by the shaft 39 and comprises a control element 42 moveable axially under the effect of conical pins 43 carried by the sliding element 35. The shaft 39 carries the heart-piece 44 for zero resetting. During the disconnection, shaft 39 is braked due to the fact that the wheel 17 is then axially pressed against the endstone of the upperbearing of the shaft An elastic washer 45, having the shape of a four gear train of the chronograph is then held at its both ends so as to prevent any slippage of the gears.

The control mechanism for the functions of the' chronograph is represented principally in FIG. 1. This mechanism comprises a rocking lever 46 for starting and stopping the control mechanism. Lever 46 is pivital about pivot point 47 on the frame. A force indicated by the arrow 48 may be applied to lever 46 by means of a pusher not represented carried by the casing of the watch. The rocking lever 46 carries, articulated thereon by means of a circular portion 49a, a finger 49 submitted to the action of a spring 50 provided with a heel 50a articulated at 51 on the frame of the movement. The heel 50a carries a pin 52 passing through a hole 53 providedin the sliding control element 29 previously disclosed. Depending on whether the sliding element 29 occupies one or the other of its two working positions, respectively represented in FIGS. 4 and l, in each of which position it is maintained by a jumper 54, the spring 50 occupies also one or the other of two positions, under the effect of the edges of the hole 53 acting on the pins 52. In one of said positions,'spring 50 maintains the finger 49 opposite a portion 29a of the sliding element, and in the other of said positions the spring maintains this finger opposite a reverse lever 55 articulated in 56 on the frame of the movement. Lever 55 is provided with a portion 55a engaged into a slot 57 of the sliding element 29. The result is that whatever may be the position of the sliding element 29, the pressure exerted at 48 on the rocking lever 46 brings the sliding element into its other position, the finger 49 acting either directly on the sliding element, by means of the portion 29a thereof, or indirectly by the intermediary of the reverse lever 55.

The sliding element 29 acts on the one hand on the control element 26 of the first coupling mechanism, carrying the conical pins 27, and on the other hand, by means of a finger 29b, on a locking lever 58 intended to lock the sliding element 35 previously measured and which carries the control pins 36 of the second coupling mechanism and the control pins 43 of the third one. This sliding element 35, which is operated by means of a second pusher, not represented, acting at 59, carries over three pins 60, 61 and 62 operating respectively three resetting to zero hammers 63, 64 and 65 which cooperate respectively with the heart-pieces 30, 37 and 44 for resetting the second, minute and hour counters. The sliding member 35 is provided with a portion 35a operating a brake 66 intended to act, by its end 66a, on the portion of larger diameter 18b of the shaft 18 for braking the shaft when the first coupling device is in the uncoupled position, while releasing this shaft during the resetting to zero operation.

Owing to the locking member 58, the sliding member 35 of the resetting to zero mechanism can be operated only when the sliding member 29 for starting and stopping the chronograph occupies the position represented in FIG. 4, corresponding to the stopping.

It is to be noted that the watch comprises a small second hand, not represented, carried by a wheel 67 (FIG. 5) driven by the second wheel 5 by the intermediary of an intermediary wheel 68.

What we claim is:

1. A chronograph timepiece comprising, a timepiece movement including a frame and a gear train, a chronograph mechanism mounted at a first driven end thereof in derivation on the gear train for driving the chronograph mechanism, a chronograph coupling device and a locking device positioned on the chronograph mechanism at said driven end, the chronograph coupling device and the locking device comprise a common control element, the coupling and locking devices being arranged such that the control element is operable between a first working position in which a driven element is coupled and released and a second working position in which the driven element is disconnected and locked, and a braking device positioned on the chronograph mechanism at the terminal end thereof opposite said driven end thereof, whereby upon disconnection of the movement from the mechanism the gear train of the mechanism is held at both ends by said locking and braking devices to prevent any slippage of gears in the gear train.

2. A timepiece as claimed in claim 1 in which the chronograph mechanism includes a plurality of counters including a seconds counter, a plurality of coupling devices respectively connecting the counters to the gear train, the chronograph mechanism includes a mechanism for resetting the same to zero, said counter coupling devices being operable to release the counters upon operation of the resetting to zero mechanism, such that resetting of the counters may be effected without driving the gear train.

3. A timepiece as claimed in claim 2 in which the counter coupling device for the seconds counter is the same as said chronograph coupling device, said chronograph coupling device being arranged to permit the first gear of the gear train to be disconnected from the movement and also to permit disconnection of the seconds counter therefrom.

4. A timepiece as claimed in claim 1 in which the chronograph coupling device and the locking device comprise a common control element, the coupling and locking devices being arranged such that the control device is operable between a first working position in which a driven element is coupled and released and a second working position in which the driven element is disconnected and locked.

5. A timepiece as claimed in claim 1 in which the coupling device and the locking device together comprise a combined mechanism including a driving element and a driven element, said driving element and driven element being freely coaxially mounted on a common shaft, the shaft having a first shoulder and a ,second shoulder, one of said driving element and driven element bearing against said first shoulder with the other of said driving element and driven element interposed on the shaft between the shoulders, a spring bearing on the second shoulder to maintain the driving element or driven element in bearing engagement with the first shoulder and with each other to maintain their connection in rotation, the control element being operable on the spring so as to axially displace the spring and the driving and driven elements, whereby operation of the control element will displace the driven element to a position adjacent the frame of the movement to lock the driven element and simultaneously disconnect and free the driving and driven elements one from each other.

6. A timepiece as claimed in claim 5 in which the chronograph mechanism includes a seconds counter and the shaft includes an indicating element for the seconds counter, a braking device operable on the shaft when the chronograph mechanism is disconnected from the gear train so as to maintain the position of the indicating element.

7. A timepiece as claimed in claim 5 in which the first shoulder has a generally frustoconical shaped surface and the element which bears against said first shoulder has a corresponding shaped surface.

8. A timepiece as claimed in claim 1 in which the chronograph mechanism includes at least a sliding and rocking lever having axially directed embossments, each embossment having an inclined plane, the control element including an axially moveable disc shaped element having a plurality of holes corresponding in number to the embossments, each embossment being positioned in a respective hole on the disc, such that the rocking lever is moveable between a first position in which each embossment is positioned coaxial with its respective hole and the disc shaped member is not driven by the rocking lever, and a second position in which the inclined planes of the embossments act on the edges of the holes to axially move the disc shaped member and thereby cause disconnection and locking of the driven element.

9. A timepiece as claimed in claim 8 in which the chronograph mechanism includes a seconds counter and an hours counter and a minutes counter, each counter having a coupling device, and there are two rocking levers having said embossments, one of said rocking levers being operable on one coupling device and the other rocking lever being operable on the remaining two coupling devices.

10. A timepiece as claimed in claim 9 in which the chronograph mechanism includes a mechanism for resetting the same to zero and a starting and stopping pusher, the one said rocking lever operates the coupling device positioned at the driving end of the chronograph mechanism and also operates to release the seconds counter, the other said rocking lever operates to release the minutes counter and hours counter, the one said rocking lever being controlled by the starting and stopping pusher and the other said rocking lever being controlled by the resetting to zero mechanism.

11. A timepiece as claimed in claim 10 in which the chronograph mechanism includes a plurality of resetting to zero heart-pieces for the counters and the other said rocking lever operates said heart-pieces.

12. A timepiece as claimed in claim 11 in which there is a locking member operable by the action of said one rocking lever, said other rocking lever being controlled by the locking member, whereby said other rocking lever is released only when the one rocking lever is in the position corresponding to stopping of the chronograph mechanism.

13. A timepiece as claimed in claim 10 in which there is a reverse device positioned between the pusher and the one rocking lever, whereby two successive forces exerted on the pusher will move the one rocking lever alternatively in one direction or in the other.

14. A timepiece as claimed in claim 13 in which the first rocking lever has a bearing surface provided thereon and the reverse device includes an oscillating finger articulated on a movable member which is operable by the pusher, an intermediary oscillating lever operable against said one rocking lever, a return spring connected to the oscillating finger, the position of the return spring being variable with the position of said one rocking lever, such that when the return spring is in a position corresponding to a first position of the first rocking lever the oscillating finger is positioned opposite the bearing surface and a force exerted on the starting and stopping pusher directly operates the said one rocking lever, and in a second position of said one rocking lever the finger is positioned opposite the intermediary oscillating lever and a force exerted on the starting and stopping pusher acts on the oscillating lever and said first rocking lever causing the same to act as a reversing element whereby said one rocking lever is displaced in the direction opposite the direction of displacement of the finger. 

1. A chronograph timepiece comprising, a timepiece movement including a frame and a gear train, a chronograph mechanism mounted at a first driven end thereof in derivation on the gear train for driving the chronograph mechanism, a chronograph coupling device and a locking device positioned on the chronograph mechanism at said driven end, the chronograph coupling device and the locking device comprise a common control element, the coupling and locking devices being arranged such that the control element is operable between a first working position in which a driven element is coupled and released and a second working position in which the driven element is disconnected and locked, and a braking device positioned on the chronograph mechanism at the terminal end thereof opposite said driven end thereof, whereby upon disconnection of the movement from the mechanism the gear train of the mechanism is held at both ends by said locking and braking devices to prevent any slippage of gears in the gear train.
 2. A timepiece as claimed in claim 1 in which the chronograph mechanism includes a plurality of counters including a seconds counter, a plurality of coupling devices respectively connecting the counters to the gear train, the chronograph mechanism includes a mechanism for resetting the same to zero, said counter coupling devices being operable to release the counters upon operation of the resetting to zero mechanism, such that resetting of the counters may be effected without driving the gear train.
 3. A timepiece as claimed in claim 2 in which the counter coupling device for the seconds counter is the same as said chronograph coupling device, said chronograph coupling device being arranged to permit the first gear of the gear train to be disconnected from the movement and also to permit disconnection of the seconds counter therefrom.
 4. A timepiece as claimed in claim 1 in which the chronograph coupling device and the locking device comprise a common control element, the coupling and locking devices being arranged such that the control device is operable between a first working position in which a driven element is coupled and released and a second working position in which the driven element is disconnected and locked.
 5. A timepiece as claimed in claim 1 in which the coupling device and the locking device together comprise a combined mechanism including a driving element and a driven element, said driving element and driven element being freely coaxially mounted on a common shaft, the shaft having a first shoulder and a second shoulder, one of said driving element and driven element bearing against said first shoulder with the other of said driving element and driven element interposed on the shaft between the shoulders, a spring bearing on the second shoulder to maintain the driving element or driven element in bearing engagement with the first shoulder and with each other to maintain their connection in rotation, the control element being operable on the spring so as to axially displace the spring and the driving and driven elements, whereby operation of the control element will displace the driven element to a position adjacent the frame of the movement to lock the driven element and simultaneously disconnect and free the driving and driven elements one from each other.
 6. A timepiece as claimed in claim 5 in which the chronograph mechanism includes a seconds counter and the shaft includes an indicating element for the seconds counter, a braking device operable on the shaft when the chronograph mechanism is disconnected from the gear train so as to maintain the position of the indicating element.
 7. A timepiece as claimed in claim 5 in which the first shoulder has a generally frustoconical shaped surface and the element which bears against said first shoulder has a corresponding shaped surface.
 8. A timepiece as claimed in claim 1 in which the chronograph mechanism includes at least a sliding and rocking lever having axially directed embossments, each embossment having an inclined plane, the control element including an axially moveable disc shaped element having a plurality of holes corresponding in number to the embossments, each embossment being positioned in a respective hole on the disc, such that the rocking lever is moveable between a first position in which each embossment is positioned coaxial with its respective hole and the disc shaped member is not driven by the rocking lever, and a second position in which the inClined planes of the embossments act on the edges of the holes to axially move the disc shaped member and thereby cause disconnection and locking of the driven element.
 9. A timepiece as claimed in claim 8 in which the chronograph mechanism includes a seconds counter and an hours counter and a minutes counter, each counter having a coupling device, and there are two rocking levers having said embossments, one of said rocking levers being operable on one coupling device and the other rocking lever being operable on the remaining two coupling devices.
 10. A timepiece as claimed in claim 9 in which the chronograph mechanism includes a mechanism for resetting the same to zero and a starting and stopping pusher, the one said rocking lever operates the coupling device positioned at the driving end of the chronograph mechanism and also operates to release the seconds counter, the other said rocking lever operates to release the minutes counter and hours counter, the one said rocking lever being controlled by the starting and stopping pusher and the other said rocking lever being controlled by the resetting to zero mechanism.
 11. A timepiece as claimed in claim 10 in which the chronograph mechanism includes a plurality of resetting to zero heart-pieces for the counters and the other said rocking lever operates said heart-pieces.
 12. A timepiece as claimed in claim 11 in which there is a locking member operable by the action of said one rocking lever, said other rocking lever being controlled by the locking member, whereby said other rocking lever is released only when the one rocking lever is in the position corresponding to stopping of the chronograph mechanism.
 13. A timepiece as claimed in claim 10 in which there is a reverse device positioned between the pusher and the one rocking lever, whereby two successive forces exerted on the pusher will move the one rocking lever alternatively in one direction or in the other.
 14. A timepiece as claimed in claim 13 in which the first rocking lever has a bearing surface provided thereon and the reverse device includes an oscillating finger articulated on a movable member which is operable by the pusher, an intermediary oscillating lever operable against said one rocking lever, a return spring connected to the oscillating finger, the position of the return spring being variable with the position of said one rocking lever, such that when the return spring is in a position corresponding to a first position of the first rocking lever the oscillating finger is positioned opposite the bearing surface and a force exerted on the starting and stopping pusher directly operates the said one rocking lever, and in a second position of said one rocking lever the finger is positioned opposite the intermediary oscillating lever and a force exerted on the starting and stopping pusher acts on the oscillating lever and said first rocking lever causing the same to act as a reversing element whereby said one rocking lever is displaced in the direction opposite the direction of displacement of the finger. 